Reduced friction retention of a data storage cartridge within a storage cell

ABSTRACT

A method according to one embodiment includes inserting a data storage cartridge into an opening in a housing, the housing having a retention tab in the housing for engaging with a notch of the data storage cartridge for retaining the data storage cartridge in the housing. The retention tab has a texture. The texture of the retention tab is configured to reduce a force necessary for removing the data storage cartridge from the housing.

BACKGROUND

This disclosure relates to the retention of data storage cartridgeswithin a storage cell.

Automated data storage libraries are known for providing cost effectivestorage and retrieval of large quantities of data. The data in automateddata storage libraries is stored on data storage media that are, inturn, stored on storage cells or the like inside the library in afashion that renders the media, and its resident data, accessible forphysical retrieval. Such media is commonly termed “removable media.”Data storage media may comprise any type of media on which data may bestored and which may serve as removable media, including but not limitedto magnetic media (such as magnetic tape or disks), optical media (suchas optical tape or disks), electronic media (such as PROM, EEPROM, flashPROM, MRAM, Compactflash®, Smartmedia®, Memory Stick®, etc.), or othersuitable media. Typically, the data stored in automated data storagelibraries is resident on data storage media that is contained within acartridge and referred to as a data storage cartridge. An example of adata storage cartridge that is widely employed in automated data storagelibraries for mass data storage is a magnetic tape cartridge.

SUMMARY

A method according to one embodiment includes inserting a data storagecartridge into an opening in a housing, the housing having a retentiontab in the housing for engaging with a notch of the data storagecartridge for retaining the data storage cartridge in the housing. Theretention tab has a texture. The texture of the retention tab isconfigured to reduce a force necessary for removing the data storagecartridge from the housing.

A method according to another embodiment includes removing a datastorage cartridge through an opening in a housing, the data storagecartridge being in the housing prior to the removing. The housing has aretention tab in the housing that is engaged with a notch of the datastorage cartridge for retaining the data storage cartridge in thehousing when the data storage cartridge is in the housing. The retentiontab has a texture. The texture of the retention tab reduces a forcenecessary for removing the data storage cartridge from the housing.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention are understood by referring to thefigures in the attached drawings, as provided below.

FIG. 1 illustrates automated data storage library with the viewspecifically depicting a library having a left hand service bay,multiple storage frames and a right hand service bay in accordance withan embodiment of the invention;

FIG. 2 illustrates an automated data storage library with the viewspecifically depicting an exemplary basic configuration of the internalcomponents of a library in accordance with an embodiment of theinvention;

FIG. 3 is a block diagram of an automated data storage library with thediagram specifically depicting a library that employs a distributedsystem of modules with a plurality of processor nodes in accordance withan embodiment of the invention;

FIG. 4 is a block diagram depicting an exemplary controllerconfiguration in accordance with an embodiment of the invention;

FIG. 5 illustrates a front and rear view of a data storage drive inaccordance with an embodiment of the invention;

FIG. 6 illustrates a data storage cartridge in accordance with anembodiment of the invention;

FIG. 7 illustrates a storage cell in accordance with an embodiment ofthe invention;

FIG. 8 illustrates the insertion and removal of a data storage cartridgefrom a storage cell and in accordance with and embodiment of theinvention; and

FIG. 9 illustrates a data storage cartridge inserted in a storage cellin accordance with and embodiment of the invention

Features, elements, and aspects of the invention that are referenced bythe same numerals in different figures represent the same, equivalent,or similar features, elements, or aspects, in accordance with one ormore embodiments.

DETAILED DESCRIPTION

Automated data storage libraries include one or more accessors to movedata storage cartridges between storage cells and to data storagedrives. The storage cells must retain the data storage cartridges suchthat outside influences such as normal machine or door opening orclosing operations etc. do not cause the data storage cartridges to moveout of the storage cells. However, the retention force of the storagecell must still be easily overcome by an accessor removing or addingcartridges to the storage cell. Retention tabs in a storage cell may beused to engage with a notch in a data storage cartridge to retain thedata storage cartridge in the slot. The notch of the data storagecartridge, and the data storage cartridge itself, have generally smoothsurfaces. Similarly, the retention tab of the storage cell, and thestorage cell itself, have generally smooth surfaces. The smooth surfaceof the notch of the data storage cartridge comes into contact with thesmooth surface of the retention tab of the storage cell and the datastorage cartridge is retained in the storage cell by a certain amount offriction. However, in some cases, the amount of friction between theretention tab and notch is too high such that the accessor is not ableto remove the data storage cartridge from the storage cell. Further, theamount of friction between the retention tab and notch is not consistentfor each data storage cartridge and its respective storage cell, suchthat accessor may be able to remove some data storage cartridges fromtheir respective storage cells, but not be able to remove others. Theseissues may result in the accessor being unable to remove one or moredata storage cartridges from their respective storage cells causingdowntime for the automated data storage library.

Described are embodiments of an invention for a textured interfacebetween a notch of a data storage cartridge and a retention tab of astorage cell to provide a consistent and low friction force that retainsthe data storage cartridge within the cell but allows the accessor toeasily remove the data storage cartridge when needed. In one embodiment,the retention tab of a storage cell includes at least one texturedsurface. In another embodiment, the notch on a data storage cartridgeincludes at least one textured surface.

The storage cell includes a housing for storing a data storage cartridgeand includes an opening for inserting and removing a data storagecartridge. A retention tab within the housing engages with the notch ofthe data storage cartridge to retain the data storage cartridge with thehousing. In one embodiment, the retention tab of a storage cell includesat least one textured surface. In another embodiment, the notch on adata storage cartridge includes at least one textured surface. Thetextured surface reduces the contact surface between the retention taband the notch of the data storage cartridge. Accordingly, the reducedcontact surface between the retention tab and notch reduces the amountof friction between the retention tab and the notch. The data storagecartridge can thus be removed from the storage cell with less force thanthat required by the prior art having a generally smooth interfacebetween the notch of the data storage cartridge and the retention tab ofthe storage cell

Further, the textured surface allows for a more consistent amount offriction between the notch and retention tab for each data storagecartridge and its respective storage cell. This consistent amount offriction between the notch and retention tab allows for the amount forcerequired to move one data storage cartridge from its respective storagecell to be close to the amount of force required to move another datastorage cartridge from its respective storage cell. Thus, a consistentamount of force can be applied by the accessor to remove each datastorage cartridge from their respective storage cells. Thus, thetextured interface between notch of the data storage cartridge and theretention tab allows for a low and consistent force to remove aplurality of data storage cartridges from their respective storagecells.

It will be obvious, however, to one skilled in the art, that embodimentsof the present invention may be practiced without some or all of thesespecific details. In other instances, well known process operations havenot been described in detail to prevent obscuring the embodiments of thepresent invention described herein.

It is understood that all surfaces have a certain amount of texture.Therefore, for purposes of the description herein, a textured surface isa surface that has more texture than an immediate surrounding area. Forexample, in the embodiment in which the retention tab of a storage cellhas a textured surface, the retention tab is said to have a texturedsurface when the textured surface has more texture than that of theimmediate surrounding area (e.g. the sidewall of the storage cell if theretention tab is provided on a sidewall of the storage cell) Similarly,in the embodiment in which the notch of the data storage cartridge has atextured surface, the notch is said to have a textured surface when thetextured surface of the notch has more texture than that of theimmediate surrounding area (e.g. the sidewall of the data storagecartridge if the notch is provided on the sidewall of the data storagecartridge). Accordingly, a non-textured surface or a smooth surface isdefined herein as a surface that has the same amount of texture or lesstexture than an immediate surrounding area.

This invention is described in preferred embodiments in the followingdescription with reference to the Figures, in which like numbersrepresent the same or similar elements. While this invention isdescribed in terms of the best mode for achieving this invention'sobjectives, it will be appreciated by those skilled in the art thatvariations may be accomplished in view of these teachings withoutdeviating from the spirit or scope of the invention. The invention willbe described as embodied in an automated data storage library for use ina data processing environment. Although the invention shown usedmagnetic tape cartridges, one skilled in the art would recognize thatthe invention equally applies to optical disk cartridges or otherremovable storage media.

Turning now to the Figures, FIGS. 1 and 2 illustrate an automated datastorage library 10 which stores and retrieves data storage cartridgescontaining data storage media (not shown) in storage cells 16. It isnoted that references to “data storage media” herein refer to datastorage cartridges, and for purposes herein the two terms may be usedsynonymously. An example of an automated data storage library which maybe used in the described embodiments is the IBM® 3584 UltraScalable TapeLibrary, and has a configuration as depicted in FIGS. 1 and 2. Thelibrary of FIG. 1 comprises a left hand service bay 13, one or morestorage frames 11, and right hand service bay 14. As will be discussed,a frame may comprise an expansion component of the library. Frames maybe added or removed to expand or reduce the size and/or functionality ofthe library. Frames may comprise additional storage cells, drives,import/export stations, accessors, operator panels, etc.

FIG. 2 shows an example of a storage frame 11, which is the base frameof the library 10 and is contemplated to be the minimum configuration ofthe library. In this minimum configuration, there is only a singleaccessor (i.e., there are no redundant accessors) and there is noservice bay. The library 10 is arranged for accessing data storage mediain response to commands from at least one external host system (notshown), and comprises a plurality of storage cells 16, on front wall 17and rear wall 19 for storing data storage cartridges that contain datastorage media; at least one data storage drive 15 for reading and/orwriting data with respect to the data storage media; and a firstaccessor 18 for transporting the data storage media between theplurality of storage cells 16 and the data storage drive(s) 15. The datastorage drives 15 may be optical disk drives or magnetic tape drives, orother types of data storage drives as are used to read and/or write datawith respect to the data storage media. The storage frame 11 mayoptionally comprise an operator panel 23 or other user interface, suchas a web-based interface, which allows a user to interact with thelibrary. The storage frame 11 may optionally comprise an upper I/Ostation 24 and/or a lower I/O station 25, which allows data storagemedia to be inserted into the library and/or removed from the librarywithout disrupting library operation. The library 10 may comprise one ormore storage frames 11, each having storage cells 16 accessible by firstaccessor 18.

As described above, the storage frames 11 may be configured withdifferent components depending upon the intended function. Oneconfiguration of storage frame 11 may comprise storage cells 16, datastorage drive(s) 15, and other optional components to store and retrievedata from the data storage cartridges. The first accessor 18 comprises agripper assembly 20 for gripping one or more data storage media and mayinclude a bar code scanner 22 or other reading system, such as acartridge memory reader or similar system, mounted on the gripper 20, to“read” identifying information about the data storage media.

FIG. 3 illustrates an embodiment of an automated data storage library 10of FIGS. 1 and 2, which employs a distributed system of modules with aplurality of processor nodes. An example of an automated data storagelibrary which may implement the distributed system depicted in the blockdiagram of FIG. 3, and which may implement the described embodiments, isthe IBM 3584 UltraScalable Tape Library.

While the automated data storage library 10 has been described asemploying a distributed control system, the described embodiments may beimplemented in automated data storage libraries regardless of controlconfiguration, such as, but not limited to, an automated data storagelibrary having one or more library controllers that are not distributed.The library of FIG. 3 comprises one or more storage frames 11, a lefthand service bay 13 and a right hand service bay 14. The left handservice bay 13 is shown with a first accessor 18. As discussed above,the first accessor 18 comprises a gripper assembly 20 and may include areading system 22 to “read” identifying information about the datastorage media. The right hand service bay 14 is shown with a secondaccessor 28. The second accessor 28 comprises a gripper assembly 30 andmay include a reading system 32 to “read” identifying information aboutthe data storage media. In the event of a failure or otherunavailability of the first accessor 18, or its gripper 20, etc., thesecond accessor 28 may perform some or all of the functions of the firstaccessor 18. The two accessors 18, 28 may share one or more mechanicalpaths or they may comprise completely independent mechanical paths. Inone example, the accessors 18, 28 may have a common horizontal rail withindependent vertical rails. The first accessor 18 and the secondaccessor 28 are described as first and second for descriptive purposesonly and this description is not meant to limit either accessor to anassociation with either the left hand service bay 13, or the right handservice bay 14.

In the exemplary library, first accessor 18 and second accessor 28 movetheir grippers in at least two directions, called the horizontal “X”direction and vertical “Y” direction, to retrieve and grip, or todeliver and release the data storage media at the storage cells 16 andto load and unload the data storage media at the data storage drives 15.

The exemplary library 10 receives commands from one or more host systems40, 41 or 42. The host systems, such as host servers, communicate withthe library directly, e.g., on path 80, through one or more controlports (not shown), or through one or more data storage drives 15 onpaths 81, 82, providing commands to access particular data storage mediaand move the media, for example, between the storage cells 16 and thedata storage drives 15. The commands are typically logical commandsidentifying the media and/or logical locations for accessing the media.The terms “commands” and “work requests” are used interchangeably hereinto refer to such communications from the host system 40, 41 or 42 to thelibrary 10 as are intended to result in accessing particular datastorage media within the library 10.

The exemplary library is controlled by a distributed control systemreceiving the logical commands from hosts, determining the requiredactions, and converting the actions to physical movements of firstaccessor 18 and/or second accessor 28.

In the exemplary library, the distributed control system comprises aplurality of processor nodes, each having one or more processors. In oneexample of a distributed control system, a communication processor node50 may be located in a storage frame 11. The communication processornode provides a communication link for receiving the host commands,either directly or through the drives 15, via at least one externalinterface, e.g., coupled to line 80.

The communication processor node 50 may additionally provide acommunication link 70 for communicating with the data storage drives 15.The communication processor node 50 may be located in the frame 11,close to the data storage drives 15. Additionally, in an example of adistributed processor system, one or more additional work processornodes 52, 252 are provided, which may comprise, e.g., a work processornode 52 that may be located at first accessor 18, and that is coupled tothe communication processor node 50 via a network 60, 157. Each workprocessor node may respond to received commands that are broadcast tothe work processor nodes from any communication processor node, and thework processor nodes may also direct the operation of the accessors,providing move commands. One or more XY processor nodes 55, 255 areprovided, which may comprise, e.g., an XY processor node 55 located atan XY system of first accessor 18. The XY processor node 55 is coupledto the network 60, 157, and is responsive to the move commands,operating the XY system to position the gripper 20.

Also, an operator panel processor node 59 may be provided at theoptional operator panel 23 for providing an interface for communicatingbetween the operator panel and the communication processor node 50, thework processor nodes 52, 252, and the XY processor nodes 55, 255.

A network, for example comprising a common bus 60, is provided, couplingthe various processor nodes. The network may comprise a robust wiringnetwork, such as the commercially available CAN (Controller AreaNetwork) bus system, which is a multi-drop network, having a standardaccess protocol and wiring standards, for example, as defined by CiA,the CAN in Automation Association, Am Weich Selgarten 26, D-91058Erlangen, Germany. Other networks, such as Ethernet, or a wirelessnetwork system, such as RF or infrared, may be employed in the libraryas is known to those of skill in the art. In addition, multipleindependent networks may also be used to couple the various processornodes.

The communication processor node 50 is coupled to each of the datastorage drives 15 of a storage frame 11, via lines 70, communicatingwith the drives and with host systems 40, 41 and 42. Alternatively, thehost systems may be directly coupled to the communication processor node50, at input 80 for example, or to control port devices (not shown)which connect the library to the host system(s) with a library interfacesimilar to the library/drive interface. As is known to those of skill inthe art, various communication arrangements may be employed forcommunication with the hosts and with the data storage drives 15. In theexample of FIG. 3, host connections 80 and 81 are SCSI busses. Bus 82comprises an example of a Fibre Channel bus which is a high speed serialdata interface, allowing transmission over greater distances than theSCSI bus systems.

The data storage drives 15 may be in close proximity to thecommunication processor node 50, and may employ a short distancecommunication scheme, such as SCSI, RS-422, USB (Universal Serial Bus),SAS (Serial Attached SCSI), etc. The data storage drives 15 are thusindividually coupled to the communication processor node 50 by means oflines 70. Alternatively, the data storage drives 15 may be coupled tothe communication processor node 50 through one or more networks, suchas CAN, Ethernet, etc.

Additional storage frames 11 may be provided and each is coupled to theadjacent storage frame. Any of the storage frames 11 may comprisecommunication processor nodes 50, storage cells 16, data storage drives15, and networks 60.

Further, as described above, the automated data storage library 10 maycomprise a plurality of accessors. A second accessor 28, for example, isshown in a right hand service bay 14 of FIG. 3. The second accessor 28may comprise a gripper 30 for accessing the data storage media, and anXY system 255 for moving the second accessor 28. The second accessor 28may run on the same horizontal mechanical path as first accessor 18, oron an adjacent path. The exemplary control system additionally comprisesan extension network 200 forming a network coupled to network 60 of thestorage frame(s) 11 and to the network 157 of left hand service bay 13.

In FIG. 3 and the accompanying description, the first and secondaccessors are associated with the left hand service bay 13 and the righthand service bay 14 respectively. This is for illustrative purposes andthere may not be an actual association. In addition, network 157 may notbe associated with the left hand service bay 13 and network 200 may notbe associated with the right hand service bay 14. Depending on thedesign of the library, it may not be necessary to have a left handservice bay 13 and/or a right hand service bay 14.

An automated data storage library 10 typically comprises one or morecontrollers to direct the operation of the automated data storagelibrary. Host computers and data storage drives typically comprisesimilar controllers. A controller may take many different forms and maycomprise, for example but not limited to, an embedded system, adistributed control system, a personal computer, or a workstation.Essentially, the term “controller” as used herein is intended in itsbroadest sense as a device that contains at least one processor, as suchterm is defined herein. FIG. 4 shows a typical controller 400 with aprocessor 402, RAM (Random Access Memory) 403, nonvolatile memory 404,device specific circuits 401, and I/O interface 405. Alternatively, theRAM 403 and/or nonvolatile memory 404 may be contained in the processor402 as could the device specific circuits 401 and I/O interface 405. Theprocessor 402 may comprise, for example, an off-the-shelfmicroprocessor, custom processor, FPGA (Field Programmable Gate Array),ASIC (Application Specific Integrated Circuit), discrete logic, or thelike. The RAM (Random Access Memory) 403 is typically used to holdvariable data, stack data, executable instructions, and the like. Thenonvolatile memory 404 may comprise any type of nonvolatile memory suchas, but not limited to, ROM (Read Only Memory), PROM (Programmable ReadOnly Memory), EEPROM (Electrically Erasable Programmable Read OnlyMemory), flash PROM (Programmable Read Only Memory), NVRAM (Non-VolatileRandom Access Memory), MRAM (Magnetoresistive Random Access Memory),battery backup RAM, CompactFlash®, SD (Secure Digital), CD (CompactDisk), DVD (Digital Versatile Disk), hard disk drives, etc. Thenonvolatile memory 404 is typically used to hold the executable firmwareand any nonvolatile data. The I/O interface 405 comprises acommunication interface that allows the processor 402 to communicatewith devices external to the controller 400. Examples may comprise, butare not limited to, serial interfaces such as RS-232, USB (UniversalSerial Bus), SCSI (Small Computer Systems Interface), Fibre Channel,Ethernet, SAS (Serial Attached SCSI), etc. The device specific circuits401 provide additional hardware to enable the controller 400 to performunique functions such as, but not limited to, motor control of acartridge gripper. The device specific circuits 401 may compriseelectronics that provide, by way of example but not limitation, PulseWidth Modulation (PWM) control, Analog to Digital Conversion (ADC),Digital to Analog Conversion (DAC), etc. In addition, all or part of thedevice specific circuits 401 may reside outside the controller 400.

While the automated data storage library 10 is described as employing adistributed control system, the described embodiments may be implementedin various automated data storage libraries regardless of controlconfiguration, such as, but not limited to, an automated data storagelibrary having one or more library controllers that are not distributed.A library controller may comprise one or more dedicated controllers of aprior art library. For example, there may be a primary controller and abackup controller. In addition, a library controller may comprise one ormore processor nodes of a distributed control system. For example,communication processor node 50 (FIG. 3) may comprise the librarycontroller while the other processor nodes (if present) may assist thelibrary controller and/or may provide backup or redundant functionality.In another example, communication processor node 50 and work processornode 52 may work cooperatively to comprise the library controller whilethe other processor nodes (if present) may assist the library controllerand/or may provide backup or redundant functionality. Still further, allof the processor nodes may comprise the library controller. Herein,library controller may comprise a single processor or controller or itmay comprise multiple processors or controllers.

FIG. 5 illustrates an embodiment of the front 501 and rear 502 of a datastorage drive 15. In the example of FIG. 5, the data storage drive 15comprises a hot-swap drive canister. This is only an example and is notmeant to limit the invention to hot-swap drive canisters. In fact, anyconfiguration of data storage drive may be used whether or not itcomprises a hot-swap canister.

FIG. 6 illustrates an embodiment of a data storage cartridge 600. Datastorage cartridge 600 comprises data storage media (not shown). In oneembodiment, the data storage media may be magnetic tape and,accordingly, data storage cartridge 600 may be a tape cartridge. Thedata storage cartridge 600 is inserted in data storage drive 15 so thatthe data may be read and/or written to the data storage media. As shownin FIG. 6, the data storage cartridge 600 comprises a generallyrectangular housing 602 forming an exterior dimensional form factor ofthe data storage cartridge 600. The cartridge housing 602 has a top 604,a bottom 606, two sides 610, a front 612, and a back 614. A notch 608 isprovided on the data storage cartridge 600 for engaging with a retentiontab of a storage cell 16 of an automated data storage library 10. Asshown, in one embodiment the notch 608 is on a one side 610 of the datastorage cartridge 600. However, one of ordinary skill in the art wouldunderstand that the notch 608 could be provided at any location on thedata storage cartridge 600. For example, the notch 608 could be providedeither side 610 of the data storage cartridge, the top 605 or bottom607, or the front 612 or back 614 of the data storage cartridge 600, orat a plurality of locations described above.

FIG. 7 illustrates an embodiment of a storage cell 16 comprising storagecell housing 702. The housing 702 includes a pair of opposing side walls704, 706, a back wall 708, and a floor 710 which is orthogonal andconnected to the two opposing side walls 704, 706 and the back wall 710.The side walls 704, 706, back wall 708, and floor 710 define an openingfor inserting and removing data storage cartridge 600. As shown in FIG.8, the housing 702 is modular in nature and can be stacked over anotherhousing to form a larger array of a plurality of storage cells 16. Forexample, FIG. 2 illustrates a plurality of storage cells 16 on frontwall 17 and rear wall 19 of an automated data storage library 10.Returning to FIG. 7, the housing 702 conforms substantially to the shapeand size of a data storage cartridge 600 with tolerances that allow theeasy and convenient insertion of the cartridge through the storage cell16 opening.

The housing 702 includes a retention tab 712 for engaging the notch 608of data storage cartridge 600 when the data storage cartridge isinserted into the storage cell 16. The retention tab 712 protrudes froma side wall 706 of the housing 702 and depresses out of the path of thedata storage cartridge when the data storage cartridge is insertedwithin the housing 712 and engages with the notch 608 of the datastorage cartridge 600. The retention tab 712, when engaged with thenotch 608 of data storage cartridge, retains the data storage cartridge600 within the storage cell 16 and prevents the data storage cartridge600 from falling out from the storage cell 16 due to outside influencessuch as machine vibration or opening or closing of a door to theautomated storage library.

In one embodiment, the retention tab 712 includes at least one texturedsurface 714 that contacts the notch 608 on data storage cartridge 600when the data storage cartridge is inserted into the storage cell 16.The textured area 714 of the retention tab 712 may include a texture ofbumps, lines or grooves or any combination including at least one ofbumps, lines, or grooves. The texture on textured surface 714 ofretention tab 712 reduces the contact surface between the retention tab712 and the notch 608 of the data storage cartridge 600. Accordingly thereduced contact surface between the retention tab 712 and the notch 608of the data storage cartridge 600 reduces the amount of friction betweenthe retention tab 712 and the notch 608 of the data storage cartridge600 such that the data storage cartridge 600 can be removed from thestorage cell 16 with less force than compared to a retention tab 712with a non-textured surface. For example, tests have shown thatproviding a textured area 714 on retention tab 712 reduces the forcerequired to pull data storage cartridge 600 from the storage cell 16 bythirty to fifty percent. Further, the textured surface 714 of theretention tab 712 allows for a more consistent force to be applied inorder remove each of the data storage cartridges from their respectivestorage cells 16.

While FIG. 7 shows that the retention tab 712 is on a side wall 706 ofthe housing 702, it should be understood that the retention tab 712could be on either side wall 704, 706 or floor 710 that corresponds withthe notch 608 of the data storage cartridge 600 when inserted into thestorage cell 16. Still further, while FIG. 7 shows that only area 714 ofretention tab 712 includes texture, one of ordinary skill in the artwould understand that the entire retention tab 712 may be textured, orthat other surfaces that contact the notch 608 of data storage cartridge600 may be textured. Finally, it should be understood that while thetexture in the present embodiment is described to only include bumps,lines and grooves, one of ordinary skill in the art should understandthat the texture on texture surface 714 of retention tab may be anytexture that reduces the contact surface between the retention tab 712and the notch 608 of the data storage cartridge 600.

Returning to FIG. 6, in one embodiment, the notch 608 of data storagecartridge 600 includes at least one textured surface 616. Still further,in one embodiment, the notch 608 of data storage cartridge 600 includesat least one textured surface that contacts the retention tab 712 whenthe data storage cartridge 600 is inserted into storage cell 16. Thetextured area 616 of the notch may include a texture of bumps, lines, orgrooves or any combination including at least one of bumps, lines, orgrooves. The texture on textured surface 616 of the notch 608 reducesthe contact surface between the retention tab 712 and the notch 608 ofthe data storage cartridge 600. Accordingly the reduced contact surfacebetween the retention tab 712 and the notch 608 of the data storagecartridge 600 reduces the amount of friction between the retention tab712 and the notch 608 of the data storage cartridge 600 such that thedata storage cartridge 600 can be removed from the storage cell 16 withless force than compared to a notch with a non-textured surface. Forexample, test have shown that providing a textured area 616 on notch 608of the data storage cartridge 600 reduces the force required to pulldata storage cartridge 600 from the storage cell 16 by thirty to fiftypercent. Further, the textured surface 616 of the notch 608 of the datastorage cartridge 600 allows for a more consistent force to be appliedin order remove each of the data storage cartridges from theirrespective storage cells 16.

While FIG. 6 shows that only area 616 of notch 608 includes texture, oneof ordinary skill in the art would understand that the entire notch 608may be textured, or that other surfaces that contact the retention tab712 of the storage cell 16 may be textured. Finally, it should beunderstood that while the texture in the present embodiment is describedto only include bumps, lines and grooves the texture on texture surface616 of notch 608 may be any texture that reduces the contact surfacebetween the retention tab 712 and the notch 608 of the data storagecartridge 600.

The textured surface 616 of the notch 608 and the textured surface 714of the retention tab 712 can be provided by any means. In one embodimentthe textured surface may be molded, over-molded, roughened, or scraped,however, the invention should not be limited to these methods. Further,while the above description includes in which the either the retentiontab 712 may have a textured surface 714 or the notch 608 of the datastorage cartridge 600 may have a textured surface 616, one of ordinaryskill in the art would understand, that in one embodiment, both theretention tab 712 and the notch 608 may have textured surfaces.

FIG. 8 illustrates an embodiment of data storage cartridge 600 isinserted and removed from the storage cell 16 of an automated datastorage library 10. In one embodiment, the data storage cartridge 600 isinserted and removed from the storage cell 16 by accessor 18 with agripper assembly 20. The accessor 18 inserts data storage cartridge 600with the back 614 of the data cartridge housing 602 facing the back wall708 of the storage cell housing 702. As shown in FIG. 8, the notch 608of the data storage cartridge 600 aligns with the retention tab 712. Asthe accessor 18 inserts the data storage cartridge 600 in the storagecell the retention tab 712 depresses out of the path of the data storagecartridge 600 and engages with the notch 608 of the data storagecartridge 600.

FIG. 9 illustrates data storage cartridge 600 inserted within thestorage cell 16. The retention tab 712 is engaged with the notch 608 ofthe data storage cartridge 600. The retention tab 712 contacts the notch608 along a textured interface. For example, area 714 of retention tab712 may contact area 616 of notch 608 when the data cartridge is fullyinserted within the storage cell 16. In one embodiment, area 714 ofretention tab is textured. In another embodiment area 616 of notch 608as textured. In yet another embodiment, both areas 714 of the retentiontab and area 616 of notch 608 are textured. By providing textured areas714 and/or 616 the contact surface between the retention tab 712 and thenotch 608 of the data storage cartridge 600 is reduced. The texture oftextured areas 616 and 714 may include a texture of bumps, lines orgrooves or any combination including at least one of bumps, lines, orgrooves. Still further, the texture may include any texture thatincreases the surface area of the textured areas 714 and 616 theretention tab 712 and notch 608, respectively.

Returning to FIG. 8, the accessor 18 removes the data storage cartridge600 from the storage cell 16 by applying a force, F, in the directionindicated by FIG. 8. The reduced contact surface between the retentiontab 712 and the notch 608 of the data storage cartridge 600 reduces theamount of friction between the retention tab 712 and the notch 608 ofthe data storage cartridge 600 such that the data storage cartridge 600can be removed from the storage cell 16 with less force than compared totwo non-textured surfaces in contact. Further, the textured surface onone of at least the notch 608 of the data storage cartridge 600 and theretention tab 712 of the storage cell allows for a more consistentforce, F, to be applied to remove each of the data storage cartridgesfrom their respective storage cells. Therefore, an accessor may be ableto provide a low and consistent force to remove a plurality of datastorage cartridges from their respective storage cells.

As described, embodiments of the present invention allow for a texturedinterface between a notch of a data storage cartridge and a retentiontab of a storage cell to provide a consistent and low friction forcethat retains the data storage cartridge within the cell but allows theaccessor to easily remove the data storage cartridge when needed. Thetextured surface reduces the contact surface between the retention taband the notch of the data storage cartridge. Accordingly, the reducedcontact surface between the retention tab and notch reduces the amountof friction between the retention tab and the notch. The data storagecartridge can thus be removed from the storage cell with less force thanthat required by the prior art having a generally smooth interfacebetween the notch of the data storage cartridge and the retention tab ofthe storage cell. Further, the textured surface allows for a moreconsistent amount of friction between the notch and retention tab foreach data storage cartridge and its respective storage cell such that aconsistent amount of force can be applied by the accessor to remove eachdata storage cartridge from their respective storage cells.

The foregoing description of embodiments of the invention has beenpresented for the purposes of illustration and description. It is notintended to be exhaustive or to limit the embodiments to the preciseform disclosed. Many modifications and variations are possible in lightof the above teaching. It is intended that the scope of the embodimentsbe limited not by this detailed description, but rather by the claimsappended hereto. The above specification, examples and data provide acomplete description of the manufacture and use of the composition ofthe embodiments. Since many embodiments may be made without departingfrom the spirit and scope of the embodiments, the embodiments reside inthe claims hereinafter appended or any subsequently-filed claims, andtheir equivalents.

What is claimed is:
 1. A method, comprising: inserting a data storagecartridge into an opening in a housing, the housing having a retentiontab in the housing for engaging with a notch of the data storagecartridge for retaining the data storage cartridge in the housing,wherein the retention tab has a texture, wherein the texture of theretention tab is configured to reduce a force necessary for removing thedata storage cartridge from the housing.
 2. The method of claim 1,wherein the housing includes a pair of opposing side walls, a back wall,and a floor orthogonal and connected to the side walls and the backwall, and wherein the side walls, back wall, and floor, define theopening for inserting and removing the data storage cartridge, whereinthe retention tab protrudes from at least one side wall of the housing.3. The method of claim 1, wherein the retention tab depresses out of apath of the data storage cartridge when the data storage cartridge isinserted in the housing and engages with the notch of the data storagecartridge when the data storage cartridge is fully inserted in thehousing.
 4. The method of claim 1, wherein the retention tab has atleast one textured surface that contacts the notch on a side wall of thedata storage cartridge when the data storage cartridge is inserted intothe housing.
 5. The method of claim 1, wherein the texture of theretention tab comprises bumps.
 6. The method of claim 1, wherein thetexture of the retention tab comprises lines.
 7. The method of claim 1,wherein the texture of the retention tab comprises grooves.
 8. Themethod of claim 1, wherein the data storage cartridge is inserted intothe opening by an accessor.
 9. The method of claim 1, wherein thehousing is part of a storage cell in an automated data storage libraryhaving an array of storage cells.
 10. The method of claim 9, wherein thedata storage cartridge is inserted into the opening by an accessor. 11.The method of claim 1, comprising removing the data storage cartridgefrom the housing.
 12. A method, comprising: removing a data storagecartridge through an opening in a housing, the data storage cartridgebeing in the housing prior to the removing; wherein the housing has aretention tab in the housing that is engaged with a notch of the datastorage cartridge for retaining the data storage cartridge in thehousing when the data storage cartridge is in the housing, and whereinthe retention tab has a texture, wherein the texture of the retentiontab reduces a force necessary for removing the data storage cartridgefrom the housing.
 13. The method of claim 12, wherein the housingincludes a pair of opposing side walls, a back wall, and a floororthogonal and connected to the side walls and the back wall, andwherein the side walls, back wall, and floor, define the opening forinserting and removing the data storage cartridge, wherein the retentiontab protrudes from at least one side wall of the housing.
 14. The methodof claim 12, wherein the retention tab depresses out of a path of thedata storage cartridge when the data storage cartridge is inserted inthe housing and engages with the notch of the data storage cartridgewhen the data storage cartridge is fully inserted in the housing. 15.The method of claim 12, wherein the retention tab has at least onetextured surface that contacts the notch on a side wall of the datastorage cartridge when the data storage cartridge is inserted into thehousing.
 16. The method of claim 12, wherein the texture of theretention tab comprises bumps.
 17. The method of claim 12, wherein thetexture of the retention tab comprises lines.
 18. The method of claim12, wherein the texture of the retention tab comprises grooves.
 19. Themethod of claim 12, wherein the data storage cartridge is inserted intothe opening by an accessor.
 20. The method of claim 12, wherein thehousing is part of a storage cell in an automated data storage libraryhaving an array of storage cells.